Improvement in blast-furnaces



S. WILKESY,

Blast -Furnace.

' -UNrrnn STATES ArnN'r muon.

SAMUEL ILKES, OF HAMMONDSVILLE, OHIO.

IMPROVEMENT IN BLAST-FURNACES.

Specification forming part of Letters Patent No. ESAS?, dated September8, 1857.

`Waking of Iron; and I do hereby declare that the following is a fulland exact description thereof, reference being had to the accompanyingdrawings, and to the letters of reference marked thereon.

Figures l and 2 represent an elevation of a blast-furnace with theapplication of my invention, and Fig. 8 is a sectional view of the samefurnace through the center from side to side.

A is the top, and B the bottom,of theboshes. C is the main pipe leadingfrom the steamboiler; c c c c, branch pipes leading off into thefurnace; a a aa, points at which the pipes enter the furnace; b b b b b,valves in the several pipes.

The nature of my invention consists in the introduction of the steam,whether with or without being previously passed through a heatingapparatus, into blast-furnaces at the boshes instead of, as heretofore,at the tuyeres or with. the blast.

To enable others skilled in the art to make use of my invention, I willproceed to describe its application and operation.

The means and apparatusby which the steam is generated are immaterial tothe effect and may be adapted to local circumstances or sitnation. Thegeneration of steam in sufficient quantity at a convenient location nearthe furnace so that a supply of steam as wanted may be readily procuredto be introduced into the furnace is the essential thing, and for thispurpose any of kthe ordinary means may be em ployed where a steam-engineis used upon the premises for other purposes. The same boiler maysupplythe steam to be introduced into the furnace, or a boiler maybeerected for the eX- press purpose. The steam is introduced into thefurnace at different points in its circumference and at various heights,(within the limit of the boshes, howeven) as at a a a, a, in order thatit may have the more full and free access to every portion of thecontents within the boshes at the same time. It is desirable, however,that the number of points at which steam is introduced should not be toogreatly multiplied, as the consequent increase of apertures in themasonry of the furnace will have a tendency to weaken its solidity. Fromfour to six points is the most convenient number.

In furnaces already built the apertures through which it is designed toinsert the pipes for the introduction of the steam will have to bedrilled through the surrounding brick or stone work and the masonry ofthe boshes. In building furnaces these apertures may be convenientlychanneled or cut in the upper or lower faces of the stones or fire-brickforming the inside of the boshes before they are laid, and openings leftto correspond in building up the surrounding brick or stone work orstack. Through these apertures and openings the pipes conveying thesteam from the boiler are to be laid or'inserted. These pipes may be ofcast or wroughtiron, or any suitable material. They need not be largerin diameter than half an inch, and should be contracted at the openinginto the furnace to a diameter of from one-eighth to one-quarter of aninch. The greater the number of points at which the steam is introducedinto the furnace the smaller should be the diameters of the severalpipes at their openings into the furnace. The pipes may all be suppliedfrom a single pipe leading from the boiler, and from which they canbranch off in any convenient arrangement'. The apertures through thestones or fire-brick forming the boshes should not be of greater sizethan just to admit of the insertion of the pipes. The openings in thestack may more conveniently'be made larger. The pipes should be providedwith valves, in order that the flow of steam maybe regulated andcontrolled. There may be either a single valve in the main pipe or onein each of the branch pipes, or both.

The latter is the best arrangement.

The object of the introduction or application of the steam to the chargeof the furnace at the boshes is to secure a thorough oXidiza-tion of theiron ore, mine, or stone by bringing in contact with it in the processof its reduction at the point at which the chemical action of thefurnace is in most active progress the gaseous elements of water, thuseffecting that change in the ore which presents it to the action of theiire during the melting in the state most favorable for a perfectand'rapid production of iron therefrom. v

In regard to the quantity of steam to be introduced and the time of itsintroduction, no

certain and uniform rule can be laid down. The size and kind of furnace,the nature and q uality of the materials used, the character of thedraft, and the state or condition of the furnace at any particular timewill all require attention. By means of the Valves in the several pipesthe supply of steam can be regulated with due regard to the varyingcircumstances. Care must be taken in the introduction of the steam, asshould a large quantity be introduced at once its sudden and greatexpansion under the intense heat of the furnace would produce tooviolenta disturbance of the charge and might result in an explosion.Until the furnace is fully fired and under Way but little if anyV steamneed be introduced, as until the melting of the iron ore, mine, or stonehas commenced the material is not in condition for the proper and mostbeneficial action of the steam.

If it is desired to heat the steam before it is introduced into thefurnace, it may be passed through a heating apparatus of any of theforms used for heating air fora hot-blast. By having a distinct seriesof pipes passing through the same apparatus and exposed to the same heatas the pipes for heating the air for the blast,'the same res may be madeto answer for both the blast and the steam. The additional expense andtrouble, however, necessary to be incurred to heat the steam will morethan counterbalance, as a general thing, the advantage to be gained,especially Where the steam-boiler from which.V the supply of steam isbrought is so near to the furnace that no material cooling orcondensation can take place in the passage of the steam from the boilerto the furnace. It may in some cases, however, be found, owing to localand special circumstances, that the expense and trouble Will bejustified by the additional advantage gained in heating the steam. Afterthe steam has passed through the heating apparatus, it is introducedinto the furnace in the same manner as when it is not heated.

I have described a particular manner in which the steam may be appliedat the boshes; but I do not mean to limit myself to this particularmanner, as the essence of my invention is not in the particularmechanical means and appliances used for the purpose, but in theVdiscovery of the most advantageous point at which steam should beintroduced into the furnace in the smelting and making of iron; and as Ihave invented and described ameans by which my discovery may bepractically employed and used, I desire to secure the benefit of mydiscovery and invention by Letters Patent.

I do not claim the use of steam in thesmelting and making of iron.

NVhat I claim as my invention, and desire to secure by Letters Patent,is-

The introduction and application of steam in blast-furnaces at theboslies,\vhether at one or more points, substantially in the manner asherein described.

SAM. VVILKES.

Witnesses:

DENNIS MEAD, WILLIAMS OGLE.

